An Introduction to Electric Power Plants

1. An Introduction toElectric Power Plants Jeffrey R. Regester

2. In order to understand this...

3. E&M Principles Types of Power Plants Power System Components Outline

4. energy = “the ability to do work” measured in Joules power = rate of energy generation or use measured in Watts = Joules / sec current = rate of charge flow measured in Amps voltage = “pressure” pushing current measured in Volts Principles Water pipes analogy

5. electromagnets Moving Electrons Create Magnetic Fields DEMO: electromagnet & compass on overhead

6. generators speakers Magnetic Fields Push on Moving Electronsor moving magnetic fields push on stationary electrons DEMO: force on current apparatusDEMO: make current with magnet & coil

7. Why do we need “mechanical means”? It takes a force to push a conductor through a magnetic field — inertia won’t due. The Purpose of a Power Plant is toTurn a Loop of Wire in a Magnetic Field Car alternator... DEMO: copper tubeDEMO: GeneconsDEMO: Al plate and mag

8. Powerhouse @ Hoover Dam

9. Types of Power Plants Classification by the “mechanical means” used to turn the generator... • Thermal (water steam by burning Coal, Oil, NG) • Nuclear (water steam by Uranium or Plutonium fission) • Geothermal • Hydroelectric (falling water) • Wind Solar...

10. Thermal Power Plant

12. Nuclear Power Plant

14. Hydroelectric Power Plant

15. Hoover Itaipu

16. ELECTRICAL Generators & Turbines Transformers Switches Busses Circuit Breakers Capacitor Banks MECHANICAL Conveyors Silos Boilers Scrubbers & Stacks Pumps Cooling Towers Power Plant Components

17. Conveyors Boilers Scrubbers and Stacks Pumps Cooling Towers At the front end

18. The whole point of the power plant is to turn the generators to produce electrical energy. Generators

19. Difficult to replace A spare is often kept Turbines

20. uninsulated electrical conductors large cross-section = low resistance must be far from ground and other components to avoid arcing Busses flirthermography.com

21. Switches & Switchyards http://www.learnz.org.nz/trips06/images/big/b-switchyard.jpg

22. PURPOSE: to change the voltage increase = “step-up” decrease = “step-down” Often run hot, must be cooled, prone to explode. oil inside cooling fins and fans blast walls Transformers DEMO: pass around small transformer DEMO: two coils, one with meter, other with battery

23. PURPOSE: stop the flow of current if too much flows (due to short circuit or excess demand) 230 kV breaker Circuit Breakers DEMO: blow room breaker

24. Purpose: to smooth out spikes or “glitches” in the line voltage. Capacitor Banks DEMO:charge/discharge a cap DEMO:Lenz’s Law

25. Transmission Lines and the “grid”

26. Why are High Voltages Used? • Transmission lines typically carry voltages of 110 kV, 230 kV, or even higher. The wires are not insulated, so they are kept high off the ground and well separated from each other, to prevent arcing (sparks) and injury or people or animals. • Why use such high voltages? Using very high voltages on the transmission lines reduces the amount of energy wasted heating up the wires. • And why is that so? Transformers cannot add energy, so if the voltage is increased, the current (in amps) must decrease. The charges flowing through the wires constantly collide with the atoms, losing energy and heating the wire. We call this resistance. Recall that the power (energy per time) lost to that heating is given by the equation P=I2R. If the current is reduced, the power used in heating the wire is reduced.

27. Transformer Sub-Station Purpose: to reduce the very high voltages from the transmission lines (>100kV) to intermediate voltages used to serve an individual town or section of a city (typically 66 kV or 33 kV) TTR Substations, Inc.

28. To your house... smaller transformers (on power line poles or green boxes on the ground) reduce the voltage further to the 240V delivered to individual homes